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Bioceramic scaffolds with two-step internal/external modification of copper-containing polydopamine enhance antibacterial and alveolar bone regeneration capability

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 65-82页

作者： Xiaojian jiang Lihong LEI Weilian SUN Yingming WEI Jiayin HAN Shuaiqi ZHONG Xianyan YANG Zhongru gou Lili CHEN Department of Oral Medicine the Second Affiliated HospitalZhejiang University School of MedicineHangzhou310009China Bio-nanomaterials and Regenerative Medicine Research Division Zhejiang–California International Nanosystem InstituteZhejiang UniversityHangzhou310058China

Magnesium-doped calcium silicate(CS)bioceramic scaffolds have unique advantages in mandibular defect repair;however,they lack antibacterial properties to cope with the complex oral microbiome.Herein,for the first time,the CS scaffold was functionally modified with a novel copper-containing polydopamine(PDA(Cu^(2+)))rapid deposition method,to construct internally modified(*P),externally modified(@PDA),and dually modified(*P@PDA)scaffolds.The morphology,degradation behavior,and mechanical properties of the obtained scaffolds were evaluated in vitro.The results showed that the CS*P@PDA had a unique micro-/nano-structural surface and appreciable mechanical resistance.During the prolonged immersion stage,the release of copper ions from the CS*P@PDA scaffolds was rapid in the early stage and exhibited long-term sustained release.The in vitro evaluation revealed that the release behavior of copper ions ascribed an excellent antibacterial effect to the CS*P@PDA,while the scaffolds retained good cytocompatibility with improved osteogenesis and angiogenesis effects.Finally,the PDA(Cu^(2+))-modified scaffolds showed effective early bone regeneration in a critical-size rabbit mandibular defect model.Overall,it was indicated that considerable antibacterial property along with the enhancement of alveolar bone regeneration can be imparted to the scaffold by the two-step PDA(Cu^(2+))modification,and the convenience and wide applicability of this technique make it a promising strategy to avoid bacterial infections on implants.

关键词： Copper-containing polydopamine Modification Antibacterial property Bone regeneration Angiogenesis Bioceramic scaffold

Study on the energy level limitations of triplet-triplet annihilation upconversion with anthracene-isomerized dimers as annihilators

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ChemPhysMater

ChemPhysMater 2024年第2期3卷 187-193页

作者： Shanshan Liu Tingting gou Xiaojuan Song Riming Hu Heyuan Liu Xiyou Li Xuchuan jiang Institute for Smart Materials&Engineering University of JinanJinan 250022China Schoolof Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580China

The enhancement in the efficiency of triplet-triplet annihilation upconversion(TTA-UC)is mainly determined by the triplet energy transfer(TET)and triplet-triplet annihilation(TTA)between the sensitizers and annihilators.The TET process works efficiently by adjusting the concentration ratio of the sensitizers and annihilators.The efficiency of TTA is determined by the properties of the annihilator.Because TTA is a Dexter-type energy transfer and is affected by the diffusion rate,the energy levels of the excited states and the molecular size are both crucial in TTA.In this study,four isomerized dimers of 9,10-diphenlanthracene(DPA)and anthracene(An)were designed and prepared as annihilators for TTA-UC.The singlet and triplet energy levels could be adjusted by altering the connection position while maintaining the molecular weight and size.When PtOEP was used as the sensitizer,the maximum upconversion efficiency of 9-[4-(9-anthracenyl)phenyl]-10-phenylanthracene(9DPA-9An)was~11.18%.This is four times higher than that of 9,10-diphenyl-2,9-bianthracene(2DPA-9An,2.63%).The calculation of the energies of T_(1)and the higher triplet state(T_(3),because E(T_(2))is similar to the E(T)of these dimers)for these dimers has provided insights into the underlying reasons.These indicated that the energy gap value of 2×E(T_(1))-E(T_(3))is the determining factor for TTA efficiency.This work may provide a better understanding of the excited-state energy levels,which is crucial for designing novel annihilators to enhance the TTA-UCefficiency.

关键词： Upconversion Annihilator Triplet-triplet annihilation Energy levels

A method for identifying coalbed methane co-production interference based on production characteristic curves: A case study of the Zhijin block, western Guizhou, China

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Petroleum Exploration and Development 2022年第5期49卷 1126-1137页

作者： GUO Chen QIN Yong YI Tongsheng CHEN Zhenlong YUAN Hang GAO Junzhe gou jiang College of Geology and Environment Xi'an University of Science and TechnologyXi'an 710054China Shaanxi Provincial Key Laboratory of Geological Support for Coal Green Exploitation Xi'an 710054China Geological Research Institute for Coal Green Mining Xi'an University of Science and TechnologyXi'an 710054China Key Laboratory of CBM Resources and Reservoir Formation Process Ministry of EducationChina University of Mining and TechnologyXuzhou 221116China Guizhou Bureau of Coal Geological Exploration Guiyang 550008China East China Oil&Gas Company SinopecNanjing 210011China

Efficient detection of coalbed methane(CBM) co-production interference is the key to timely adjusting the development plan and improving the co-production efficiency. Based on production data of six typical CBM co-production wells in the Zhijin block of western Guizhou Province, China, the production characteristic curves, including production indication curve, curve of daily water production per unit drawdown of producing fluid level with time, and curve of water production per unit differential pressure with time have been analyzed to explore the response characteristics of co-production interference on the production characteristic curves. Based on the unit water inflow data of pumping test in coal measures, the critical value of in-situ water production of the CBM wells is 2 m^(3)/(d·m). The form and the slope of the initial linear section of the production indication curves have clear responses to the interference, which can be used to discriminate internal water source from external water source based on the critical slope value of 200 m^(3)/MPa in the initial linear section of the production indication curve. The time variation curves of water production per unit differential pressure can be divided into two morphological types: up-concave curve and down-concave curve. The former is represented by producing internal water with average daily gas production greater than 800 m^(3)/d, and the latter produces external water with average daily gas production smaller than 400 m^(3)/d. The method and critical indexes for recognition of CBM co-production interference based on the production characteristic curve are constructed. A template for discriminating interference of CBM co-production was constructed combined with the gas production efficiency analysis, which can provide reference for optimizing co-production engineering design and exploring economic and efficient co-production mode.

关键词： coalbed methane multi-seam co-production interlayer interference production indication curve external water internal water discrimination template

重庆市绿色空间景观格局与PM_(2.5)浓度时空相关性

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地球科学与环境学报 2024年第1期46卷 25-37页

作者：苟爱萍李皖新王江波上海应用技术大学生态技术与工程学院上海201418 南京工业大学建筑学院江苏南京211816

空气中的细颗粒物对人民群众身体健康产生严重威胁,探究绿色空间景观格局对PM_(2.5)浓度的影响,有助于通过调整绿色空间格局降低PM_(2.5)浓度。以重庆市1980~2020年土地利用遥感监测数据和PM_(2.5)浓度数据作为基础数据,通过景观格局指... 详细信息

空气中的细颗粒物对人民群众身体健康产生严重威胁,探究绿色空间景观格局对PM_(2.5)浓度的影响,有助于通过调整绿色空间格局降低PM_(2.5)浓度。以重庆市1980~2020年土地利用遥感监测数据和PM_(2.5)浓度数据作为基础数据,通过景观格局指数法、空间自相关分析研究绿色空间景观格局及PM_(2.5)浓度变化特征,再通过时空地理加权回归(GTWR)模型研究绿色空间景观格局指数变化对PM_(2.5)浓度的影响及其时空异质性。结果表明:①重庆市PM_(2.5)浓度从1980年至2010年逐渐上升,2010年至今逐渐降低;同时,其空间分布具有显著聚集特征,主要显示为东部低-低聚集、西部高-高聚集的特征。②林地、草地和耕地的面积指数(TA)、斑块密度指数(PD)和斑块连接度指数(COHESION)与PM_(2.5)浓度具有显著的相关性。其中,林地面积指数呈负影响,耕地、草地面积指数呈正影响;林地、草地斑块密度指数呈正影响,耕地斑块密度指数呈负影响;林地、草地和耕地斑块连接度指数均呈负影响。③主城都市区内,草地面积指数和耕地斑块密度指数对PM_(2.5)浓度的负影响较强。渝东北三峡库区城镇群和渝东南武陵山区城镇群内,林地聚合度指数(AI)、斑块密度指数和斑块连接度指数以及耕地面积指数对PM_(2.5)浓度的影响较强。

关键词：绿色空间景观格局指数消减效应 PM_(2.5)浓度空间自相关分析时空地理加权回归模型时空异质性重庆

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双脉冲自保护药芯焊丝电弧焊工艺稳定性

焊接学报 2024年第5期45卷 90-97页

作者：张恒铭金秀鹃苟宁年蒋小霞石玗周海刘伟宁夏大学机械工程学院银川750000 兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室兰州730050 宁夏特种设备检验检测院银川750000 天地宁夏支护装备有限公司银川750021

鉴于自保护药芯焊丝在野外焊接的重要性,尤其对于野外大型机械等关键零部件的应急修复,提高其焊接成形精度至关重要,因此研究了自保护药芯焊丝在双脉冲电弧模式下的工艺稳定性.为了实现电弧焊工艺稳定性的有效控制,采用单因素试验研究... 详细信息

鉴于自保护药芯焊丝在野外焊接的重要性,尤其对于野外大型机械等关键零部件的应急修复,提高其焊接成形精度至关重要,因此研究了自保护药芯焊丝在双脉冲电弧模式下的工艺稳定性.为了实现电弧焊工艺稳定性的有效控制,采用单因素试验研究了双脉冲参数对焊接过程稳定性的影响,发现熔滴平均尺寸与电流变异系数关系密切,因此,选取强弱脉冲频率、占空比、强弱脉冲峰值和基值7个双脉冲参数作为输入值,建立一种基于RBF-BP神经网络的熔滴平均尺寸预测模型,结果表明,该预测模型有效、可行,为控制熔滴过渡过程稳定性提供了技术支撑.

关键词：自保护药芯焊丝工艺稳定性熔滴过渡 RBF-BP神经网络

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我国卫生技术人员薪酬分配公平性研究

中国卫生经济 2024年第5期43卷 1-4,22页

作者：夏冕王明欧尹圣洁蒋帅武汉大学政治与公共管理学院武汉430072 武汉大学健康治理研究中心武汉430072 郑州大学第一附属医院郑州450052 河南省医院管理研究院郑州450052

目的:通过实证数据探索我国卫生领域薪酬制度改革中存在的不足,为优化和完善我国卫生技术人员薪酬政策提供数据支持和决策参考。方法:根据中国家庭收入调查数据计算基尼系数,分析不同地区和不同性别卫生技术人员薪酬分配的公平性。结果... 详细信息

目的:通过实证数据探索我国卫生领域薪酬制度改革中存在的不足,为优化和完善我国卫生技术人员薪酬政策提供数据支持和决策参考。方法:根据中国家庭收入调查数据计算基尼系数,分析不同地区和不同性别卫生技术人员薪酬分配的公平性。结果:卫生技术人员收入呈上升趋势且在社会中位于较高水平,其中东部、城市、男性卫生技术人员获得的薪酬更高;各地区和女性群体收入分配差距正逐渐加大;卫生行业的收入分配比多数行业更平均。结论:应继续推进卫生领域薪酬制度改革,兼顾效率与公平,因地制宜制定收入分配方案,加强对女性卫生技术人员薪酬分配的关注与保护。

关键词：卫生技术人员薪酬收入基尼系数

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位移无拖曳控制的动力学协调条件研究

宇航学报 2024年第4期45卷 540-549页

作者：苟兴宇王丽娇许现民邹奎蒋庆华北京控制工程研究所北京100094 空间智能控制技术全国重点实验室北京100094 中国科学院数学与系统科学研究院科学与工程计算国家重点实验室北京100190

针对位移无拖曳控制的可实现性问题及避免推力饱和问题,首先基于位移无拖曳控制动力学方程,推导出位移无拖曳控制系统中连续可变推力推进子系统的最大推力需要满足的基本动力学协调条件。进一步由位移无拖曳控制动力学方程退化得到的切... 详细信息

针对位移无拖曳控制的可实现性问题及避免推力饱和问题,首先基于位移无拖曳控制动力学方程,推导出位移无拖曳控制系统中连续可变推力推进子系统的最大推力需要满足的基本动力学协调条件。进一步由位移无拖曳控制动力学方程退化得到的切换动力学方程,推导出负刚度加速度函数为线性及非线性函数两种情形下的让步动力学协调条件。针对让步动力学协调条件开展了仿真比对,结果表明,强非线性情形下的让步动力学协调条件比退化的线性情形更加严苛。最后通过分析给出位移无拖曳控制避免推力饱和的、定性的动力学协调条件,并得到仿真校验,即:检验质量初始状态及指令状态应在让步动力学协调条件区域内靠近负刚度力零位,开环系统时间延迟尽可能短,并且控制带宽应折中选择。

关键词：位移无拖曳控制动力学协调条件切换动力学方程 Hamilton函数检验质量状态初值

双交联废弃瓦楞纸基气凝胶缓冲材料的制备与性能

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复合材料学报 2024年第3期41卷 1458-1469页

作者：任子铭黎亮丽蒋向向岳士琪李宏达苟进胜北京林业大学木质材料科学与应用教育部重点实验室北京100083 北京林业大学木材科学与工程北京市重点实验室北京100083

以废弃瓦楞纸(WCP)为原料,明胶(G)和植酸(PA)为改性剂,采用溶胶-凝胶法制备高吸能气凝胶。对明胶用量、植酸用量和反应温度对双交联改性废纸基气凝胶力学性能的影响进行了研究,并通过SEM、FTIR、XRD和TGA表征了明胶单一改性和明胶-植酸... 详细信息

以废弃瓦楞纸(WCP)为原料,明胶(G)和植酸(PA)为改性剂,采用溶胶-凝胶法制备高吸能气凝胶。对明胶用量、植酸用量和反应温度对双交联改性废纸基气凝胶力学性能的影响进行了研究,并通过SEM、FTIR、XRD和TGA表征了明胶单一改性和明胶-植酸双交联改性前后气凝胶的结构与性能变化。结果表明:改性单体成功交联到废纸纤维上,双交联改性后的废纸基气凝胶呈现三维网状结构,相较于未改性和单一改性废纸基气凝胶具有较高的热稳定性、优异的隔热性能(0.045 W·m^(-1)·K^(-1))和超强的吸能性(应变70%时,单位体积吸收能为253.45 kJ/m^(3)),吸能性分别为珍珠棉(EPE)和乙烯-醋酸乙烯酯共聚物(EVA)的11.26和2.7倍。作为包装运输过程中的一种绿色缓冲材料,具有广阔的应用前景。

关键词：废弃瓦楞纸复合气凝胶增强改性力学性能缓冲包装材料

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夹心饼干缺陷在线检测系统的设计

电子质量 2024年第4期 47-51页

作者：苟岩岩姜辉泰山职业技术学院机电系山东泰安271000 泰安市岱岳区岳峰小学山东泰安271000

为了降低饼干企业用人成本、提升夹心饼干产品质量,设计了安装于夹心机内的小型一体化的饼干缺陷检测视觉系统和处理算法,采用分光系统将一次拍摄分别在2个相机成像,分别用于对饼胚和馅料的检测,该结构能够同时对饼胚和馅料的各种生产... 详细信息

为了降低饼干企业用人成本、提升夹心饼干产品质量,设计了安装于夹心机内的小型一体化的饼干缺陷检测视觉系统和处理算法,采用分光系统将一次拍摄分别在2个相机成像,分别用于对饼胚和馅料的检测,该结构能够同时对饼胚和馅料的各种生产过程中可能产生的缺陷进行在线检测和自动剔除。工程应用表明,该系统调试方便、检测稳定且精度高,具有良好的推广应用价值。

关键词：夹心饼干缺陷视觉检测分光系统